<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    div{
        width: 300px;
        height: 300px;

    }
</style>

<body>
    <div></div>
<script>
    // 1、自定义一个随机颜色函数
    function getRandomColor(flag = true){
        
        if(flag){
            // 3、如果是true 则返回 #ffffff
            let str = '#'
            let arr = ['0', '1', '2', '3','4','5','6','7','8','9','a','b','c','d', 'e','f',]
            for (let i = 1; i <= 6; i++){
                // 每次随机从数组里面抽取一个
                let random = Math.floor(Math.random() * arr.length)
                str =str + arr[random]
            }
            return str

        } else {
            // 4、否则是 false 则返回rgb(255,255,255)
            let r = Math.floor(Math.random() * 256)
            let g = Math.floor(Math.random() * 256)
            let b = Math.floor(Math.random() * 256)
            return `rgb(${r},${g},${b})`
        }
        
    }
    //2、调用函数 getRandomColor(布尔型)
    console.log(getRandomColor(false))
    console.log(getRandomColor(true))
    console.log(getRandomColor())


    const div = document.querySelector('div')
    div.style.backgroundColor = getRandomColor()
</script>

</body>
</html>